This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. A bead-angiogenesis model is implanted in fibrin hydrogels of varied stiffness in this study. They are furthermore treated with actin contractility inhibitors. Angiogenic vessel sprouts that develop on the beads are then analyzed in terms of actin contractility presence as well as morphological differences. The tissues are stained for actin as well as CD31 to determine the effects of contractility inhibition on capillary morphogenesis.